Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

skyhimself75

what is the solution of 5|x+1|+6=21

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    how would we start it?

    • 2 years ago
  2. Alexis1994_13
    Best Response
    You've already chosen the best response.
    Medals 0

    5|χ+1|=15 => |x+1| = 3.

    • 2 years ago
  3. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    im sure as long as you just get an answer; you will continue to type in the same kind of problem over and over again :)

    • 2 years ago
  4. Llort
    Best Response
    You've already chosen the best response.
    Medals 0

    assuming x is real: \[5 \sqrt((x+1)^2)+6 = 21\] otherwise: |x+1|=3

    • 2 years ago
  5. rauch
    Best Response
    You've already chosen the best response.
    Medals 0

    2

    • 2 years ago
  6. Llort
    Best Response
    You've already chosen the best response.
    Medals 0

    don't just give it to him.

    • 2 years ago
  7. skyhimself75
    Best Response
    You've already chosen the best response.
    Medals 0

    i don't know how to start it absolute value i just don't understand it

    • 2 years ago
  8. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    the absolute value is the last thing to work on; how do you get that absolute value all by itself?

    • 2 years ago
  9. rauch
    Best Response
    You've already chosen the best response.
    Medals 0

    5(x+1)+6=21 (5x+5)+6=21 5x+6=16 5x=10 x=2

    • 2 years ago
  10. Llort
    Best Response
    You've already chosen the best response.
    Medals 0

    looking at this question, what is the other solution for x if it was not an absolute value?

    • 2 years ago
  11. skyhimself75
    Best Response
    You've already chosen the best response.
    Medals 0

    i'm seriously terrible in math i really don't know:[

    • 2 years ago
  12. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    the term "absolute value" means that there is a quantifiable value; something that can be measured. length, height, area, volume, distance are all examples of abslute values

    • 2 years ago
  13. jgeorge123
    Best Response
    You've already chosen the best response.
    Medals 0

    dont jus give him the answer he is probably usin this site for a summer school!!!

    • 2 years ago
  14. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    in other words; an absolute value doesnt care about what direction the sign takes us in; it only cares about a quantifiable measure

    • 2 years ago
  15. Llort
    Best Response
    You've already chosen the best response.
    Medals 0

    |a| is always positive, you discount the negative answer.

    • 2 years ago
  16. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    sky, you isolate the absolute value just like you would isolate a variable. Llort, no you do not 'discount' the negative answer. It is a valid solution.

    • 2 years ago
  17. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    |-12| has the same absolute value as |12|

    • 2 years ago
  18. amistre64
    Best Response
    You've already chosen the best response.
    Medals 0

    as a result; if we are determining any value for inside of the absolute value notation; we have to account for the positive and the negative results that occur within it

    • 2 years ago
  19. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    So if you have \[5|x+1| + 6 = 21\] You want to isolate the term with the absolute value in it first. You do this by subtracting 6 from both sides of the equation.

    • 2 years ago
  20. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    What do you get when you subtract the 6?

    • 2 years ago
  21. skyhimself75
    Best Response
    You've already chosen the best response.
    Medals 0

    -2?

    • 2 years ago
  22. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    No, \(5|x+1| + 6 - 6 = 21 -6\) \[\implies 5|x+1| + 0 = 15\]\[\implies 5|x+1| = 15\]

    • 2 years ago
  23. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    So now lets say that |x+1| is something, lets call it k.. So we have \(5k = 15 \)\[\implies \frac{1}{5}\cdot5k = \frac{1}{5}15\]\[\implies k = 3\] And since we said k was |x+1| we have \[|x+1| = 3\]So what values can x have and still make this equation true?

    • 2 years ago
  24. Llort
    Best Response
    You've already chosen the best response.
    Medals 0

    I am assuming the other answer is x=-4

    • 2 years ago
  25. polpak
    Best Response
    You've already chosen the best response.
    Medals 0

    x =-4 is one solution yes, because |-4 + 1 | = |-3| = 3

    • 2 years ago
    • Attachments:

See more questions >>>

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.